Quote:
Originally Posted by rkauer
A simple approach is:
1- give the Amiga the HD stream to show the drive as HD capable.
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So this is unclear for me - i can understand how Device Self Id works but how Amiga distinguish between HD and SD floppy if there is no external signalization for HD - i assume that INDEX is measured - time between two INDEX pulses tell Amiga that floppy revolve 150 (HD) or 300 (SD) rpm?
Then adding magnet or Hall sensor we can destroy this detection
Quote:
Originally Posted by rkauer
2- hold the data to a point the Amiga can cope with it. This can be achieved by issuing several hold data (~wait) signals to the floppy as the Amiga can't manage the through output of the floppy.
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So this was one of my ideas - even some shift (FIFO) register made from DRAM like 41256 or better 411000 (1 mbit DRAM) can be used to store whole track from Index to Index - large DRAM can be used to oversample data (2x - 8x oversample can help with reading and writing data - it reduce uncertainty and error introduced in conversion), detection for half full/half empty, start write data stored in FIFO after half full (twice slower transmission to HD disk from Amiga than should be), start read from FDD by amiga also with similar rule (data transfered to and from floppy with 500kbps but Amiga is capable only to made 250kbps).
Latency is always half time between Index pulses.
Something similar to this:
http://www.nalanda.nitc.ac.in/indust...pp/xapp030.pdf